The present invention relates to an arrangement for the storage of energy in power plants where an excess of water during low-load operation is heated in the feed water preheaters, is stored as hot water in a hot storage vessel and is fed during peak-load operation into the feed water line, bypassing the feed water preheater. Alternately with the hot water, colder water is taken from, or stored, in the lower portion of the hot storage vessel.
Such a procedure is used for storing large quantities of hot water in order to handle peak loads for several hours or even several days. The advantage of this procedure is that the construction of a peak-load plant is not necessary if, instead, a few components of the medium-load power plant are strengthened or increased and the hot-water energy system is installed.
With one known procedure, the hot storage vessel is connected in parallel with the feed water preheaters. During low-load operation, hot water is stored in the upper portion of the storage vessel, while the same amount of cold water is taken from the lower portion of the hot-water storage vessel. With this procedure, difficulty is encountered because the colder water is not deaerated at the storage temperature. Hence, the hot water cannot be placed on top of the colder water without special separating elements.
In addition, the procedure described can be improved further.
Accordingly, it is an object of the present invention to provide an arrangement for storing large energy amounts for peak-load coverage for an extended period, which, on the one hand, does not require additional separating elements and which, on the other hand, makes available a large number of steam withdrawals for increasing the output.
Another object of the present invention is to provide an arrangement of the foregoing character which is substantially simple in construction and may be economically maintained in service.
A further object of the present invention is to provide an arrangement, as described, which has a substantially long operating life.